A sample of a new cleaning product, “Joe’s Famous Bleach Cleaner”, with a mass of 58.0 , was diluted with an acetic acid solution containing excess . A small amount of starch indicator solution was then added, turning the solution a deep bluish-purple. The solution was then titrated with 0.190 thiosulfate, . A volume of 37.0 of thiosulfate, the titrant, was needed to turn the solution colorless.
They give this reaction: CIO- + 2H+ + 2I- => I2 + CL- + H2O and the reaction I2+ (2SO3)^2- => 2I- + (S4O6)2-
Can somebody help me or gave me the answer of this question because I really don’t have any idea what to do.
1 Answer
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moles S2O3 2- = 0.190 M x 0.0370 L = 0.00703
moles I2 = 0.00703 / 2 =0.00352
= moles ClO-
mass NaClO = 0.00352 mol x 74.4422 g/mol = 0.262 g
% = 0.262 x 100/ 58.0 = 0.452
